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| United States Patent |
5,574,203
|
|
Noel
, et al.
|
November 12, 1996
|
Process and installation for destroying munitions containing toxic agents
Abstract
The invention relates to a process and an installation for destroying
munitions containing toxic agent. The process comprises equipping the
munitions with a pyrotechnic fragmentation device and submerging in a pool
which is filled with a liquid for neutralizing the toxic agent, closing
the pool with a lid so that the pool is sealed with respect to toxic
emanation, and igniting the pyrotechnic device so that the munitions is
fragmented and releases the toxic agent into the pool. After the
fragmentation of the munitions is neutralized with the neutralizing
liquid, the pool is reopened for another cycle of destruction. The
advantage is of completely destroying the munitions in a single operation
cycle without the risk of contamination. The invention is applicable to
the destruction of munitions containing chemical or bacteriological toxic
agents.
| Inventors:
|
Noel; Nicolas (Paris, FR);
Santo; Yves (Le Plessis Trevise, FR)
|
| Assignee:
|
Snpe Ingenierie S.A. (Saint Quentin En Yvelines, FR)
|
| Appl. No.:
|
329854 |
| Filed:
|
October 27, 1994 |
| Current U.S. Class: |
588/299; 110/237; 110/242; 149/124; 264/31; 422/129; 588/313; 588/320; 588/401; 588/403; 588/408; 588/409 |
| Intern'l Class: |
A62D 003/00 |
| Field of Search: |
588/203
149/124
264/3.1
110/237,242
422/129
|
References Cited
U.S. Patent Documents
| 3897237 | Jul., 1975 | Musselman et al. | 588/202.
|
| 4758387 | Jul., 1988 | Sayles | 264/3.
|
| 4858833 | Aug., 1989 | Hanulik | 241/24.
|
| 5458071 | Oct., 1995 | Tadmor et al. | 110/237.
|
| Foreign Patent Documents |
| 001526 | Apr., 1979 | EP.
| |
| 3913479 | Aug., 1990 | DE.
| |
| 4115435 | Aug., 1992 | DE.
| |
Primary Examiner: Mai; Ngoclan
Attorney, Agent or Firm: Cushman Darby & Cushman, LLP
Claims
We claim:
1. In a process for destroying a munition containing a toxic agent in a
pool which is filled with a neutralizing liquid for the toxic agent, the
pool also being resistant to explosions and including lid means for
closing the pool to seal against toxic emanations, the process comprising
the following cycle of operations:
(1) equipping the munition with a pyrotechnic fragmentation device;
(2) introducing the munition into the pool;
(3) closing said pool so that the pool is sealed with respect to toxic
emanation;
(4) igniting the pyrotechnic device so that the munition is fragmented and
releases the toxic agent into the neutralizing liquid;
(5) permitting the neutralizing liquid to neutralize the toxic agent; and
(6) reopening the pool after neutralization of the toxic agent for another
cycle.
2. Process according to claim 1 which comprises using, as the pyrotechnic
fragmentation device, one comprising a pyrotechnic dispersal charge of the
munition complemented by at least one initiation detonator.
3. Process according to claim 1 which comprises using, as the pyrotechnic
fragmentation device, one which comprises at least one initiation
detonator and one cutting cord located on the munition.
4. Process according to claim 1 which includes the step of recovering the
fragments of the destroyed munitions after several cycles of operation.
5. Process according to claim 4 wherein the fragments are recovered in a
receptacle placed at the bottom of the pool.
6. Process according to any one of claims 1 to 3 comprising the step of
dousing down with liquid neutralizing the toxic agent, the space lying
between the lid means for closing the pool and the surface of the
neutralizing liquid in the pool.
7. Process according to any one of claims 1 to 3 comprising the step of
agitating the neutralizing liquid in the pool during neutralization of the
toxic agent.
8. An installation for destroying munitions containing a toxic agent and
equipped with a pyrotechnic fragmentation device, said installation
comprising a pool filled with a liquid for neutralizing said toxic agent,
said pool being resistant to explosion and including lid means for sealing
said pool against toxic emanation from said pool, said lid means also
including at least one access hatch for access to said pool.
9. An installation according to claim 8 comprising means for dispensing
neutralization liquid above the surface of neutralizing liquid in the
pool.
10. An installation according to claim 9, wherein the dispensing means
operates in a closed circuit for circulating the neutralizing liquid in
the pool.
11. An installation according to claim 8 wherein the pool also includes at
least one device for agitating neutralizing liquid within the pool.
12. An installation according to claim 8, comprising two independent
preparation lines for preparing the munition for destruction and
transporting the munition from preparation to the pool.
Description
The present invention lies within the field of munitions containing
chemical or bacteriological toxic agents. Its object is to propose a
process and an installation for destroying such munitions, which process
and installation are satisfactory for the safety of the personnel and the
environment.
BACKGROUND OF THE INVENTION
Among munitions there are many of small and medium size. These are, for
example, shell, rocket, small missile warheads,. They comprise, in various
casings, generally made of metal:
a charge of chemical or bacteriological toxic agent,
a pyrotechnic dispersal charge,
an initiation system which initiates the explosion of the pyrotechnic
dispersal charge and brings about the fragmentation of the munition and
the dispersal of the toxic agent.
The initiation system is, for example, of the percussion fuse or the
proximity fuse type. During the storage of the munitions, the initiation
system is not fitted on the munition.
These munitions may also be of larger size: these are, for example, bombs
or larger missile warheads. In this case, the pyrotechnic dispersal charge
is of greater mass than for the aforementioned munitions.
We will use the general term munition in the text except where particular
points need to be stressed.
The munitions may be in a good state but voluntarily decommissioned, or
more or less damaged according to their "age" and the storage conditions
and therefore be necessarily decommissioned.
The chemical toxic agents are among those known under the name of "poison
gases" and are characterized by their suffocating, vesicant, haemotoxic or
neurotoxic action.
We will mention among suffocating gases, chlorine and phosgene
(COC1.sub.2); among vesicant agents, yperite (dichloroethylsulphide
S(CH.sub.2 -CH.sub.2 Cl).sub.2, lewisite. We will also mention other
organo-phosphorous compounds such as sarin (GB agent, (CH.sub.3).sub.2
CHOP (CH.sub.3) (O) F), tabun (GA agent, (CH.sub.3).sub.2 NP
(OCH.sub.2CH.sub.3) (O) CN), soman (GD agent, (CH.sub.3).sub.3 CCH
(CH.sub.3)OP (CH.sub.3) (O) F).
The bacteriological toxic agents are much less well known, but microbial or
vital strains are used.
By destruction of the munitions, we mean the destruction of the containers
and the contents: that is to say the destruction of the pyrotechnic
dispersal charge, the destruction (or detoxification) of the charge of
toxic agent, and finally the destruction of the casings which contain
these charges and of the "structure" of the munition so that they can be
scrapped or recycled after decontamination.
In an adjoining field, that of the treatment of hazardous industrial waste
stored in barrels, mention may be made of the process described in Patent
EP 13 822, in which the barrels are mechanically destroyed in a liquid
treatment medium which neutralizes or modifies the said waste, the residue
of which is then solidified and dumped.
The process known to date for destroying munitions consist in dismantling
the munition into its elements, in recovering the toxic agent in suitable
containers in order then to destroy the said toxic agent in specific
installations, for example by neutralization or incineration in special
furnaces (see, for example, U.S. Pat. No. 4,666,696). The pyrotechnic
dispersal charge, separated from the munition is destroyed, moreover, by
burning or blasting. Finally, the various casings and the structure of the
munition are decontaminated before being scrapped or recycled.
The drawbacks of such a set of processes are numerous: a multitude of
delicate operations on the munition which take place, moreover, in
different specific installations, with transfers from one site to another.
All this multiplies the risks as regards the personnel and the
environment. All these drawbacks are aggravated when the munitions are in
a poor state, which is frequently the case following long storage under
poor conditions.
It should also be noted, as another drawback, that such a set of processes
does not lend itself to the rapid destruction of a great number of
munitions in a short space of time.
The problem is of having available a process and an installation for
destroying the munitions containing toxic agents in a reduced number of
operations, on a single site, and this being under conditions of safety
which are satisfactory for the personnel and the environment. Another
problem is of having available a process and an installation which lend
themselves to high throughputs of destruction.
SUMMARY OF INVENTION
The present invention relates to a process for destroying, in a pool, a
munition containing a toxic agent and equipped with a pyrotechnic
fragmentation device, the pool being filled with a liquid neutralizing the
toxic agent, being resistant to explosions, and including a lid,
characterized in that the following cycle of operations is carried out:
the said pool is closed so that it is sealed with respect to toxic
emanations,
the pyrotechnic device is ignited, the fragmentation of the munition
releasing the toxic agent into the neutralizing liquid,
after the duration of neutralization of the toxic agent, the pool is
reopened for another cycle of destruction.
DETAILED DESCRIPTION OF INVENTION
The toxic emanations are the toxic agent released, when the munition is
fragmented, in the form, for example, of a gas, liquid or aerosol.
The pool and its lid which is sealed with respect to emanations, withstand
the effects of the explosion.
Preferentially, the pyrotechnic device for fragmenting the munition makes
use of the pyrotechnic dispersal charge of the said munition, complemented
by at least one detonator for initiating the operation of this pyrotechnic
dispersal charge.
In the particular cases where the munition to be destroyed does not have a
pyrotechnic dispersal charge, the pyrotechnic fragmentation device
comprises at least one initiation detonator and one cutting cord located
on the munition to create at least one opening in the munition so as to
disperse the toxic agent into the neutralizing liquid in the pool and
allow the said neutralizing liquid to enter inside the munition.
These particular cases are those, especially, of munitions initially
including a pyrotechnic dispersal charge of significant mass, which
pyrotechnic charge has been dismantled in a preliminary operation; this
precaution avoids using installations of an excessive size for
implementing the process.
The whole of the pyrotechnic fragmentation device and the firing line to
which it is connected must withstand immersion (leaktightness and
corrosion) for a space of time greater than the performance of a cycle of
destruction.
In this process the fragments of the munitions destroyed are recovered
after several cycles of destruction.
In a particular embodiment, the fragments of the munitions destroyed are
gathered in a receptacle placed at the bottom of the pool. This
receptacle, with associated handling means, serves to recover the said
fragments after several cycles of destruction.
Advantageously, the space lying between the lid of the pool and the free
surface of the neutralizing liquid in the pool is doused down with liquid
neutralizing the toxic agent. Preferentially, the said dousing down takes
place in closed circuit with the neutralizing liquid in the pool. This
dousing-down operation takes place during at least the entire duration of
the neutralization of the toxic agent.
The neutralizing liquid in the pool is agitated for at least all of the
duration of neutralization of the toxic agent, to ensure, on the one hand,
homogenization of the liquid and to ensure, on the other hand, rinsing and
decontamination of the fragments of the munitions destroyed. This
agitation thus prevents decantation of some effluents and prevents them
from concentrating at various points in the pool. The effluents are the
products resulting from the reaction of the toxic agent with the
neutralizing agent in the pool; these effluents are in solution or
suspension in the said neutralizing liquid.
Preferentially, the liquid neutralizing the toxic agent is water-based. If
necessary basic or alkaline products such as sodium hydroxide, potassium
hydroxide or other compounds promoting the neutralization reaction of the
chemical or bacteriological toxic agent are added to the water.
The excess of neutralizing liquid and its agitation by suitable devices,
and also by the effects of the explosion, contribute to increasing the
kinetics for neutralizing the toxic agent.
The neutralizing liquid in the pool is periodically checked, when it is
saturated with effluent the pool is drained and the neutralizing liquid is
renewed, the effluents being treated by suitable methods, particularly
concentration and incineration methods.
The present invention also relates to an installation for destroying
munitions containing a toxic agent and equipped with a pyrotechnic
fragmentation device. The installation comprises a pool filled with a
liquid neutralizing the said toxic agent, resistant to explosions, and
including a lid, characterized in that the said lid is equipped with at
least one access hatch which is sealed with respect to toxic emanations.
The sealed lid contains the emanations, more particularly that fraction of
toxic agent which is entrained, in the form of a gas, aerosol or liquid,
by the gas bubble and the surface shower which are created by the
explosion. Preferentially, the said lid includes an opening which is
closed in a sealed fashion by a cover.
Advantageously, the pool includes at least one device for dispersing a
neutralization liquid, emerging above the free surface of the neutralizing
liquid. This dispersing device douses down the gaseous volume lying
between the lid of the pool and its free surface in order to neutralize
the toxic agent released by the fragmentation of the munition, in the form
of a liquid, gas, or aerosol. This dispersing device also douses down all
the walls in order to decontaminate them.
Preferentially, the dispersing device operates in closed circuit with the
neutralizing liquid in the pool.
Preferentially also, the pool includes at least one device for agitating
the neutralizing liquid and make it flow through the fragments of the
munitions destroyed.
The pool includes, at the bottom part, deflectors which guide the fragments
of the munitions destroyed towards a receptacle placed at the bottom of
the pool.
The angle of inclination of the deflectors is such that the fragments of
the munitions destroyed slide over these deflectors under the action of
their weight, without remaining stuck on them by the effect of friction.
In a particular embodiment, the bottom of the pool is frustoconical and, at
its bottom part, exhibits a depression in which the said receptacle for
recovering the fragments of the munitions destroyed is housed, the
frustoconical shape of the bottom of the pool acts as the deflectors.
The pool itself is placed in a building which is sealed with respect to
emanations, and sized so as to withstand accidental explosion during
handling of the pyrotechnic device for fragmenting the munition. This
building communicates with at least one preparation line comprising a
preparation workshop in which the munition to be destroyed is equipped
with the pyrotechnic fragmentation device; with this workshop are
associated stores of munitions to be destroyed, and of initiation devices
necessary for producing a series of cycles of destruction, which will also
be denoted by the term firing.
Advantageously, the pool is associated with two preparation lines: during
one firing in the pool, the next munition is prepared in the preparation
workshop of the other preparation line.
The installation also includes a control and firing station: it is equipped
with viewing ports or a video system allowing the building of the pool to
be monitored. The displacements of the munition transporter, as well as
those of the lid for the sealed closure of the pool are controlled
remotely.
Thus, the only direct interventions of the operators on the munition are
the laying of the munition on the transporter, and the fitting of the
fragmentation initiation device (detonators and/or cutting cord); the
other operations are carried out remotely.
The advantages of the process and of the installation, which combine
pyrotechnics and chemical or bacteriological neutralization, are connected
with the destruction which takes place in a single cycle of operation on
one and the same site. This destruction is complete: the pyrotechnic
dispersal charge, the charge of toxic agent, the casings and the structure
of the munition are simultaneously destroyed. This destruction takes place
under conditions of safety which are satisfactory for the operators,
because their interventions on the munition itself are reduced to a
limited number of operations. The safety as regards the environment is
also satisfactory because the operations take place in buildings and
installations which are sealed with respect to the effluents and
dimensioned in order to withstand intentional or accidental explosions.
This process and this installation also lend themselves to carrying out the
destruction of munitions with high throughputs in order rapidly to treat a
great number of munitions.
The invention is explained in more detail below with the aid of the figures
representing a particular embodiment.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 represents a diagrammatic plan view of the destruction installation
including the pool and the auxiliary buildings.
FIG. 2 represents a diagrammatic sectional view of the pool and of the
buildings.
Before implementation of the process according to the invention, the
munitions to be destroyed are gathered together and transported to the
work site. Very defective munitions which could exhibit leaks are placed
in sealed containers, the operators wear suitable protective suits during
this phase.
On the work site, the munitions are identified and classified. One set of
munitions representing the activity of a day's work or the maximum
permissible load in the buildings is placed in the store 2 of munitions to
be destroyed, of one preparation line of the installation 1.
The operator takes, from the store 2, a munition to be destroyed, and
brings it into the preparation workshop 4: transfer takes place manually
or with the aid of a handling truck. He then fixes the said munition onto
a support 5, the cradle shape of which is designed for the dimensions of
the munition. This support is possibly consumable in order to take account
of the damage to which the fragmentation of the munition gives rise, and
thus prevent operations of checking, decontaminating, and repair before
each re-use: the support is treated like the fragments of the munition.
This support 5 is fastened under the closure cover 7 of the pool 12 by a
telescopic arm 6. This cover 7 itself is suspended from a thrust cylinder
8 under the transporter truck 9 of a monorail 10. This thrust cylinder 8
serves to lower or raise the cover 7. Like the telescopic arm 6, it is
controlled remotely.
A pyrotechnist takes, from the store 3, an initiation device and places it
on the munition. This device comprises at least one detonator when the
munition to be destroyed comprises a pyrotechnic dispersal charge, and at
least one detonator associated with at least one cutting cord when the
munition does not have the said dispersal charge. The pyrotechnist
connects the detonator to a firing line connected up to a sealed passage
located on the cover 7 and, from there connected to the control station
18. The transporter 9 is then transferred into the building 11, where the
pool 12 is to be found, above the centre of the pool 12, these operations
are controlled remotely. The pyrotechnist verifies the continuity of the
firing line then controls the lowering, by the thrust cylinder 8, of the
munition into the pool, and of the cover 7, as well as the closure of the
latter using suitable automatons, sealing as regards toxic emanations
being provided by seals.
The device 16 for dispersing, and the device 14, 15, 16 for agitating the
neutralizing liquid are started up. The pyrotechnist, after safety checks,
from the control station 18, proceeds with the firing. The fragmentation
of the pyrotechnic charge disperses the toxic agent into the neutralizing
liquid, the fragments of the munition are slowed by the liquid and fall
towards the bottom of the pool and are directed by the deflectors, here
produced by the frustoconical shape 12' of the bottom of the pool 12, to
the receptacle 17 intended to receive them. The gas bubble which
accompanies the explosion bursts at the surface, releasing part of the
toxic products into the atmosphere lying between the free surface of the
pool 12 and its lid 13. The dousing-down and agitation are maintained for
a sufficient time to ensure neutralization of the toxic agent released.
After they have been shut down the pool is reopened and the thrust
cylinder 8 raises the cover 7. The pool is ready to recommence the next
cycle of destruction with the elements coming from the other preparation
line (stores 2', 3' and workshop 4').
The dispersing or dousing-down device 16 consists, for example, of a set of
hoses equipped with calibrated perforations orientated so that they douse
down the entire volume lying between the lid and the free surface of the
neutralizing liquid, and all the surfaces and more particularly the
internal part of the cover. This device is supplied by pumps 15 which take
up the neutralizing liquid from various points 14 of the pool 12, in order
not to complicate the figure just one circuit is represented therein. The
agitating device 14, 15, 16 is here produced by the recirculation of the
neutralizing liquid. The pumps 15 take up the neutralizing liquid from
various points 14 of the bottom of the pool and supply the dispersing
device 16, and possibly various injection points on the walls of the pool,
carefully placed to ensure recirculation currents. It should be noted that
the effects of the explosion: bursting of the gas bubble, the surface
shower and the swirls which follow it, also contribute to this agitation.
The fragments, gathered in the receptacle 17, are removed from the pool at
the end of a certain number of cycles of destruction. An auxiliary
handling device serves to remove the receptacle 17, in order to unload the
fragments. After checking, the fragments are treated like ordinary waste
which is either scrapped or recycled.
When the neutralizing liquid in the pool 12 is saturated with effluents,
the liquid is evacuated by pumping to a treatment tank, the effluents and
residue of which are treated by suitable means.
The installation 1 comprises two stores 2, 2' of munitions to be destroyed,
two stores of initiation devices 3, 3' two preparation workshops 4, 4'
communicating with a building 11 in which the pool 12 is to be found. The
said pool 12 includes a lid 13, produced by sealed decking resistant to
explosions; an opening 7' made in this lid is closed so that it can be
sealed as regards toxic emanations, by a cover 7; this cover 7 fastens
under the transporter truck 9 of a monorail 10, the transporter 9 makes it
possible to bring the said cover into the preparation workshops 4 or 4'.
The two independent and parallel preparation lines (premises 2, 3, 4 and
2', 3', 4') make it possible, when a firing is being carried out in the
pool, to prepare the next firing on the other line. Independently of the
time savings, this arrangement prevents the pool from being out of service
if one of the lines is not available.
The pool 12 is hollowed out from compact and stable ground. Its bottom is
lined with concrete and the wall is produced from a ductile material which
withstands the pressure wave well and which, associated with compact
external ground, gives the whole assembly good stability. The sealing of
the pool, at the walls and ground level is provided by a flexible and
tearproof coating and it is regularly monitored to prevent risks of
pollution of the environment, that is to say of the ground and of the
groundwater table.
The pool and its lid are dimensioned to contain the effects due to the
explosion of the maximum charge of the munitions to be destroyed, this
dimensioning also takes into account the magnitude of the stresses due to
the repeated firings. For example, for the explosion of a maximum charge
of 2kg of explosive, such as TNT (trinitrotoluene) the pool must have a
diameter of approximately 12 metres, contain a height of 6 metres of
liquid, the munition to be destroyed being submerged at approximately half
depth. For dispersal charges of greater mass, installations of greater
dimensions would, of course, be required, hence the benefit in the process
of limiting the mass of the fragmentation charge by dismantling the
dispersal charge when its mass is too great.
The dousing-down device 16 and the agitating device 14, 15, 16 are,
themselves, designed and possibly protected, to withstand the effects of
repeated explosions.
Finally, all of the buildings containing the pool 12 and the stores (2, 3,
2' and 3'), the preparation workshops, are designed and dimensioned to
contain the mechanical effects (blast and fragments) and the toxic effects
(dispersal of the toxic agent) due to an accidental fragmentation of the
munition. In particular, the atmosphere of these premises is checked and
partially treated by a bubbling through the neutralizing liquid in the
pools; air locks (not represented in the figures) are provided for the
access to the various buildings.
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